I find the voting on multiple choice U.P. propositions to be just too random in nature. If 4/5 civs feels that there should be say a tax on having starbases in another civ's territory, but they all choose a different amount, they can easily lose the motion to a single, high influence vote for none. I think this just makes it unecessarily difficult to get most statutes passed when they probably should have suceeded. Perhaps it could either be a separate vote on the amount of a tax or restriction once a yes or no is decided on.

Another option would be just to introduce them with a set number and the vote would simply be yes or no like passing a bill through the US Senate. A bill may fail because the senators disagree on a single aspect of it even if they generally support the spirit behind the bill. If support for a failed bill is still strong, they can re-draft it with a few minor changes instead of just scrap it entirely.

Of course I don't expect a radical expansion of the U.P. process. Though it would be a welcome change to me to make it more of an important part of the game rather than being almost like a random event that usually amounts to being a mild annoyance. Maybe there could be a system where each civ would get a chance to introduce a proposal (round robin style starting with a random civ) so that a player could at least try to get a law passed that they might want even though they have no more control of whether or not it passes.